Conventional articles of athletic footwear include two primary elements, an upper and a sole structure. The upper provides a covering for the foot that securely receives and positions the foot with respect to the sole structure. In addition, the upper may have a configuration that protects the foot and provides ventilation, thereby cooling the foot and removing perspiration. The sole structure is secured to a lower surface of the upper and is generally positioned between the foot and the ground. In addition to attenuating ground reaction forces and absorbing energy (i.e., imparting cushioning), the sole structure may provide traction and control potentially harmful foot motion, such as over pronation. Accordingly, the upper and the sole structure operate cooperatively to provide a comfortable structure that is suited for a wide variety of ambulatory activities, such as walking and running.
The upper forms a void on the interior of the footwear for receiving the foot. The void has the general shape of the foot, and access to the void is provided by an ankle opening. Accordingly, the upper extends over the instep and toe areas of the foot, along the medial and lateral sides of the foot, and around the heel area of the foot. A lacing system is often incorporated into the upper to selectively increase the size of the ankle opening and permit the wearer to modify certain dimensions of the upper, particularly girth, to accommodate feet with varying proportions. In addition, the upper may include a tongue that extends under the lacing system to enhance the comfort of the footwear, and the upper may include a heel counter to limit movement of the heel.
Various materials may be utilized in manufacturing the upper. Some uppers are formed of knit material, such as thread and/or yarn. Knit uppers have appearances that differ from the appearances of uppers formed of other materials like leather, synthetic leather, and rubber. During the design and manufacturing of a knit upper it is common for a designer to create a design and then for one or more other people to program a knitting machine to manufacture the upper. The separation of parts of the design and manufacturing process can result in the development and manufacturing of several uppers before the designer approves a design that can be manufactured by a knitting machine. Multiple rounds or cycles of creating many knit uppers that don't meet a designer's view of the design imagined can be costly in time and resources.
Therefore, there is a need in the art for systems and methods that can allow designers, during the design process, the ability to electronically visualize knit uppers that more realistically embody a manufactured knit upper, so as to allow for timely adjusting designs prior to manufacturing. Such functionality can drastically improve the design to manufacturing process in knit engineering.